wcap-16996-np-a, rev 1, 'realistic loca evaluation ... · 26.2 v. c. summer nuclear power plant ......

Westinghouse Non-Proprietary Class 3

WCAP-16996-NP-A November 2016 Revision 1

Realistic LOCA Evaluation Methodology Applied to the Full Spectrum of Break Sizes (FULL SPECTRUM LOCA Methodology)

Volume lII FULL SPECTRUM LOCA Uncertainty Methodology and Demonstration Plant Analysis

WESTINGHOUSE NON-PROPRIETARY CLASS 3

Westinghouse Electric Company LLC 1000 Westinghouse Drive

Cranberry Township, PA 16066, USA

© 2016 Westinghouse Electric Company LLC All Rights Reserved

WCAP-16996-NP-A.docx

WCAP-16996-NP-A Revision 1

Realistic LOCA Evaluation Methodology Applied to the Full Spectrum of Break Sizes

(FULL SPECTRUM LOCA Methodology)

Jeffrey R. Kobelak LOCA Integrated Services Dr. Katsuhiro Ohkawa LOCA Integrated Services Dr. Liping Cao LOCA Integrated Services Aaron M. Everhard LOCA Integrated Services Dr. Jun Liao LOCA Integrated Services Nikolay P. Petkov LOCA Integrated Services Michael A. Shockling LOCA Integrated Services

November 2016

Prepared by: Jeffrey R. Kobelak* LOCA Integrated Services

Reviewer: Michael A. Shockling* LOCA Integrated Services

Approved: Amy J. Colussy*, Manager LOCA Integrated Services

AP1000, FSLOCA, FULL SPECTRUM, ZIRLO, and Optimized ZIRLO are trademarks or registered trademarks of Westinghouse Electric Company LLC, its affiliates and/or its subsidiaries in the United States of America and may be registered in other countries throughout the world. All rights reserved. Unauthorized use is strictly prohibited. Other names may be trademarks of their respective owners.

*Electronically approved records are authenticated in the electronic document management system.

i


TABLE OF CONTENTS

LIST OF TABLES ........................................................................................................................................ v

LIST OF FIGURES .................................................................................................................................... vii

VOLUME III

25 PLANT SOURCES OF UNCERTAINTY .................................................................................. 25-1 25.1 PLANT PHYSICAL CONFIGURATION ..................................................................... 25-1 25.2 PLANT INITIAL OPERATING CONDITIONS ........................................................... 25-7

25.2.1 Core Power Parameters ................................................................................. 25-8 25.2.2 Plant Fluid Conditions ................................................................................. 25-25

25.3 REACTOR ACCIDENT BOUNDARY CONDITIONS ............................................. 25-45 25.4 MODEL PARAMETERS ............................................................................................ 25-49 25.5 OPERATOR ACTIONS ............................................................................................... 25-49

25.5.1 EOP Sequences for a Small Break LOCA ................................................... 25-50 25.5.2 Variability of Plant Conditions Due to Operation Actions .......................... 25-51

25.6 CONTAINMENT RESPONSE .................................................................................... 25-57 25.7 PUMP LOCKED ROTOR ........................................................................................... 25-58 25.8 REFERENCES ............................................................................................................ 25-62

26 WCOBRA/TRAC-TF2 MODEL OF PILOT PLANTS .............................................................. 26-1 26.1 MODELING APPROACH ............................................................................................ 26-1

26.1.1 Introduction ................................................................................................... 26-1 26.1.2 Modeling Consistency ................................................................................... 26-2 26.1.3 Conclusions ................................................................................................... 26-5

26.2 V. C. SUMMER NUCLEAR POWER PLANT .......................................................... 26-10 26.2.1 V. C. Summer WCOBRA/TRAC-TF2 Nodalization ................................... 26-10 26.2.2 V. C. Summer Reference Case and Allowable Plant

Operating Conditions .................................................................................. 26-17 26.2.3 Plant Operating Range ................................................................................. 26-21

26.3 BEAVER VALLEY UNIT 1 NUCLEAR POWER PLANT ........................................ 26-34 26.3.1 Beaver Valley Unit 1 WCOBRA/TRAC-TF2 Nodalization ........................ 26-34 26.3.2 Beaver Valley Unit 1 Reference Case and Allowable Plant

Operating Conditions .................................................................................. 26-41 26.3.3 Plant Operating Range ................................................................................. 26-45

26.4 STEADY STATE CALCULATION/CALIBRATION ................................................. 26-64 26.5 REFERENCES ............................................................................................................ 26-67

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TABLE OF CONTENTS (cont.)

27 REFERENCE BREAK SPECTRUM ANALYSIS ..................................................................... 27-1 27.1 LARGE, INTERMEDIATE, AND SMALL BREAK SPECTRA ................................. 27-1

27.1.1 V. C. Summer (CGE) Break Spectra ............................................................. 27-1 27.1.2 Beaver Valley Unit 1 (DLW) Break Spectra ................................................ 27-26

27.2 V. C. SUMMER (CGE) REFERENCE TRANSIENTS .............................................. 27-49 27.2.1 CGE Large Break Reference Transient Description .................................... 27-49 27.2.2 CGE Intermediate Break Reference Transient Description ......................... 27-64 27.2.3 CGE Small Break Reference Transient Description .................................... 27-76

27.3 BEAVER VALLEY UNIT 1 (DLW) REFERENCE TRANSIENTS ........................... 27-91 27.3.1 DLW Large Break Reference Transient Description ................................... 27-91 27.3.2 DLW Intermediate Break Reference Transient Description ...................... 27-106 27.3.3 DLW Small Break Reference Transient Description ................................. 27-118

28 SCOPING AND SENSITIVITY STUDIES ............................................................................... 28-1 28.1 LARGE BREAK SCOPING STUDY RESULTS ......................................................... 28-3

28.1.1 Axial Power Distributions – LBLOCA ......................................................... 28-3 28.1.2 Offsite Power Availability – LBLOCA ....................................................... 28-17 28.1.3 Time Step and Convergence Criteria Studies – LBLOCA .......................... 28-32 28.1.4 Break Path Resistance – LBLOCA ............................................................. 28-43 28.1.5 Treatment of Accumulator Elevation – LBLOCA ....................................... 28-82 28.1.6 Steam Generator Hydraulics: Tube Plugging – LBLOCA .......................... 28-93

28.2 SMALL BREAK SCOPING STUDY RESULTS ..................................................... 28-108 28.2.1 Small Break Reference Transient .............................................................. 28-108 28.2.2 Axial Power Distributions – SBLOCA ..................................................... 28-108 28.2.3 Initial and Accident Boundary Conditions and

Offsite Power – SBLOCA ......................................................................... 28-128 28.2.4 Time Step and Convergence Criteria Studies – SBLOCA ........................ 28-150 28.2.5 Treatment of Accumulator Elevation – SBLOCA ..................................... 28-157 28.2.6 Break Location in the Accumulator and SI Lines – SBLOCA .................. 28-161 28.2.7 Break Orientation Studies – SBLOCA ...................................................... 28-171 28.2.8 Interfacial Drag in the Core (Level Swell) – SBLOCA ............................ 28-187 28.2.9 Steam Generator Hydraulics: Tube Plugging – SBLOCA ........................ 28-205 28.2.10 Steam Generator Hydraulics: Interfacial Drag – SBLOCA ...................... 28-219 28.2.11 Loop Seal Clearance – SBLOCA .............................................................. 28-236 28.2.12 Horizontal Stratified Flow (HS_SLUG) – SBLOCA ................................ 28-244

29 ASSESSMENT Of UNCERTAINTY ELEMENTS ................................................................... 29-1 29.1 GENERATION OF MODEL UNCERTAINTY PARAMETERS AND

RANGING DISTRIBUTIONS .................................................................................... 29-12 29.1.1 Break Flow – [

]a,c ........................ 29-12 29.1.2 Broken Cold-Leg Nozzle Flow Resistance (KN) and

Broken Loop Pump Resistance ................................................................... 29-21 29.1.3 Delivery and Bypassing of ECC – Bounding Approach ............................. 29-23

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29.1.4 Condensation in the Downcomer ................................................................ 29-23 29.1.5 Interfacial Drag in the Core Region [ ]a,c ............ 29-24 29.1.6 Cold Leg Condensation (KCOSI) ................................................................ 29-32 29.1.7 Horizontal Stratified Flow Regime Transition Boundary (HS_SLUG) ....... 29-33 29.1.8 Minimum Film Boiling Temperature (Tmin) ................................................. 29-33 29.1.9 Steam Binding and Entrainment – Bounding Approach .............................. 29-42 29.1.10 Non Condensable Gases/Accumulator Nitrogen – Bounding Approach ..... 29-42 29.1.11 Uncertainty in Loop Seal Clearance Phenomenon ...................................... 29-42 29.1.12 Steam Generator Thermal-Hydraulics ......................................................... 29-46

29.2 BREAK LOCATION, TYPE (SPLIT VS. DEGCL) AND SPLIT BREAK AREA .... 29-47 29.2.1 [ ]a,c .................................................................. 29-48 29.2.2 Determination of the Minimum Break Area (Amin) ..................................... 29-49 29.2.3 Break Type and Split Break Area Uncertainty Methodology ...................... 29-49 29.2.4 Modeling of DEGCL Breaks and Break Flow Uncertainty ......................... 29-54 29.2.5 Modeling of Split Breaks and Break Flow Uncertainty .............................. 29-57 29.2.6 Compliance with Regulatory Guide 1.157 on Break Type and Size ........... 29-61

29.3 REVIEW OF PLANT SCOPING STUDIES AND UNCERTAINTY IN PLANT INPUT PARAMETERS ................................................................................. 29-62 29.3.1 Bounded Parameters .................................................................................... 29-62 29.3.2 Initial and Boundary Conditions (Ranged Parameters) ............................... 29-64 29.3.3 Uncertainty Associated with Maximum Time Step Size ............................. 29-67

29.4 CORE AND FUEL ROD MODEL UNCERTAINTIES .............................................. 29-68 29.4.1 Initial Reactor State Uncertainties ............................................................... 29-68 29.4.2 Hot Rod Local Models Uncertainty ............................................................. 29-90 29.4.3 Fuel Rod: Uncertainty on Heat Transfer to the Fluid ................................ 29-118

29.5 EVALUATION MODEL BIASES AND UNCERTAINTY (EMDAP STEP 20) ...... 29-137 29.5.1 Fuel Rod .................................................................................................... 29-137 29.5.2 Core ........................................................................................................... 29-138 29.5.3 Upper Head ................................................................................................ 29-140 29.5.4 Upper Plenum ............................................................................................ 29-141 29.5.5 Steam Generator ........................................................................................ 29-142 29.5.6 Pump Suction Piping/Loop Seal ................................................................ 29-143 29.5.7 Pump .......................................................................................................... 29-143 29.5.8 Cold Leg/Safety Injection .......................................................................... 29-144 29.5.9 Accumulator .............................................................................................. 29-146 29.5.10 Downcomer ............................................................................................... 29-146 29.5.11 Lower Plenum ........................................................................................... 29-148 29.5.12 Break.......................................................................................................... 29-148

29.6 EXPERIMENTAL UNCERTAINTIES (EMDAP STEP 9) ....................................... 29-149 29.7 REFERENCES .......................................................................................................... 29-150

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30 TECHNICAL BASIS OF STATISTICAL PROCEDURES APPLIED IN FULL SPECTRUM LOCA UNCERTANTY METHODOLOGY .............................................. 30-1 30.1 STATISTICAL METHODOLOGY ROADMAP .......................................................... 30-1 30.2 STATISTICAL SAMPLING APPROACH (MONTE CARLO) ................................... 30-4 30.3 NON-PARAMETRIC ORDER-STATISTICS TOLERANCE LIMITS

FORMULATION ........................................................................................................... 30-5 30.3.1 Tolerance Intervals and Sample Size ........................................................... 30-10

30.4 [ ]a,c ... 30-10 30.5 OVERVIEW OF FULL SPECTRUM LOCA STATISTICAL PROCEDURE ............ 30-11 30.6 CONCLUSIONS ON COMPLIANCE WITH 10 CFR 50.46

ACCEPTANCE CRITERIA ........................................................................................ 30-13 30.6.1 [ ]a,c ..................................................................... 30-13 30.6.2 [ ]a,c ............................................................ 30-13

30.7 REFERENCES ............................................................................................................ 30-15

31 FULL SPECTRUM LOCA DEMONSTRATION ANALYSIS .................................................. 31-1 31.1 DEVELOPMENT OF INITIAL MATRIX .................................................................... 31-1

31.1.1 Break Area Ranges ........................................................................................ 31-2 31.1.2 Plant Operating Range ................................................................................... 31-2

31.2 ANALYSIS EXECUTION ............................................................................................ 31-6 31.2.1 [ ]a,c ...................................... 31-7 31.2.2 [ ]a,c ............. 31-13 31.2.3 Conclusion ................................................................................................... 31-14

31.3 ANALYSIS OF RESULTS [ ]a,c ..................................................... 31-14 31.4 ANALYSIS OF RESULTS [ ]a,c .................................................... 31-41 31.5 SUMMARY REPORT AND COMPLIANCE WITH 10 CFR 50.46 CRITERIA ....... 31-56

32 METHODOLOGY SUMMARY ................................................................................................ 32-1 32.1 COMPLIANCE WITH 10 CFR 50.46 ........................................................................... 32-1 32.2 COMPLIANCE WITH REGULATORY GUIDE 1.203 ................................................ 32-2

32.2.1 Regulatory Position 1, “Evaluation Model Development and Assessment Process” ..................................................................................... 32-2

32.2.2 Regulatory Position 2, “Quality Assurance” ............................................... 32-15 32.2.3 Regulatory Position 3, “Documentation” .................................................... 32-15 32.2.4 Regulatory Position 4, “General Purpose Computer Programs” ................. 32-16 32.2.5 Regulatory Position 5, “Graded Approach to Applying the

EMDAP Process” ........................................................................................ 32-17 32.3 COMPLIANCE WITH REGULATORY POSITION WITH

RESPECT TO THE UNCERTAINTY METHODOLOGY ......................................... 32-17 32.3.1 Regulatory Position 4, “Estimation of Overall

Calculational Uncertainty” .......................................................................... 32-17 32.4 METHODOLOGY LIMITATIONS ............................................................................. 32-21 32.5 REFERENCES ............................................................................................................ 32-21

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LIST OF TABLES

VOLUME III

Table 25.2-1 Hot Assembly Rod Power Census Summary for Westinghouse Fuel ....................... 25-29

Table 25.2-2 Peaking Factor Uncertainties .................................................................................... 25-29

Table 25.2-3 Rod Bow FQ Uncertainties ........................................................................................ 25-30

Table 25.2-4 Typical Westinghouse Plant Operation Parameters .................................................. 25-30

Table 25.5-1 Condensed EOPs for Indian Point Unit 2, Short-Term Portion ................................ 25-54

Table 26.1-1 Core Section Axial Cell Lengths ................................................................................ 26-7

Table 26.1-2 Hot Leg Noding Comparison ..................................................................................... 26-8

Table 26.1-3 Steam Generator Noding Comparison ........................................................................ 26-8

Table 26.1-4 Crossover Leg Noding ................................................................................................ 26-8

Table 26.1-5 Cold Leg Noding ........................................................................................................ 26-9

Table 26.2-1 Key LOCA Parameters and Scoping Study Values for V. C. Summer ..................... 26-22

Table 26.3-1 Key LOCA Parameters and Scoping Study Values for Beaver Valley Unit 1 .......... 26-46

Table 26.4-1 Criteria for an Acceptable Steady-State .................................................................... 26-66

Table 28.1.3-1 DTMAX Values used in LBLOCA Timestep Sensitivity ......................................... 28-33

Table 28.1.3-2 PCT Results When Varying DTMAX, CGE LBLOCA Sensitivity .......................... 28-33

Table 28.1.3-3 PCT Results When Varying DTMAX, DLW LBLOCA Sensitivity ......................... 28-34

Table 28.1.4-1 Scenarios for Break Path Resistance Sensitivity Study ............................................ 28-43

Table 28.2.9-1 [ ]a,c ...................... 28-206

Table 28.2.12-1 Flow Regime Flags ................................................................................................. 28-246

Table 28.2.12-2 [ ]a,c ............ 28-247

Table 28.2.12-3 [ ]a,c ........... 28-248

Table 29-1 Uncertainty Elements – Break Location, Type, Orientation and Area Sampling Methodology ...................................................................................... 29-5

Table 29-2 Uncertainty Elements – Thermal-Hydraulic Models .................................................. 29-6

Table 29-3a Uncertainty Elements – Local Models [ ]a,c .................................... 29-7

Table 29-3b Burst Strain for [ ]a,c ............................................................................ 29-9

Table 29-4 Uncertainty Elements – Power-Related Parameters Defined in Section 29.4.1 ....... 29-10

Table 29-5 Uncertainty Elements - Initial and Boundary Conditions Considered in Uncertainty Methodology Defined in Section 29.3.2 ............................................... 29-11

Table 29.1.2-1 Nozzle Loss Coefficient Assessment Data Base ....................................................... 29-22

vi


LIST OF TABLES (cont.)

Table 29.2.3-1 [ ]a,c .......................................................................................... 29-52

Table 29.3.2-1 Comparison of Measured and Calculated Accumulator Line Resistances ............... 29-66

Table 29.4.1-1 [ ]a,c .......................................................... 29-77

Table 29.4.2-1 Packing Fractions Using Various Measurements .................................................... 29-108

Table 29.4.2-2a Zircaloy Rate Constants (Total Oxygen) ................................................................ 29-112

Table 29.4.2-2b [ ]a,c ......................................................................................... 29-112

Table 29.4.2-3 Predictions Using Equation 29.4.2-8 and Cathcart-Pawel ...................................... 29-113

Table 29.4.3-1 [ ]a,c .................................................... 29-124

Table 29.4.3-2 [ ]a,c ................ 29-124

Table 30-1 [ ]a,c ............................................................. 30-16

Table 30-2 [ ]a,c................... 30-17

Table 30-3 Generic Rod Power Census Used for Core-Wide Oxidation Assessment ................ 30-18

Table 31.1-1 Nominal and Uncertainty Range of Plant Specific Uncertainty Contributors ............ 31-3

Table 31.1-2a [ ]a,c ..................................................... 31-4

Table 31.1-2b [ ]a,c ..................... 31-4

Table 31.1-2c [ ]a,c ...................... 31-4

Table 31.1-3 [ ]a,c ......................................................................... 31-5

Table 31.2-1 [ ]a,c ............................................................................. 31-8

Table 31.2-2a [ ]a,c ..................................................... 31-13

Table 31.2-2b [ ]a,c .................................................. 31-13

Table 31.3-1a Uncertainty Attributes [ ]a,c .................. 31-17

Table 31.3-1b Results for [ ]a,c .......................................... 31-18

Table 31.4-1a Uncertainty Attributes [ ]a,c ................ 31-43

Table 31.4-1b Results [ ]a,c ....................................... 31-44

Table 31.5-1 [ ]a,c ................................................................................................... 31-57

Table 32-1 Summary of Assessment Results and Uncertainty Treatment for High PIRT Ranked Phenomena .................................................................................. 32-4

vii


LIST OF FIGURES

VOLUME III

Figure 25.2-1 Typical Assembly Power Map and Assembly Power Distribution, Beginning of Cycle ............................................................................................ 25-31

Figure 25.2-2 Typical Assembly Power Map and Assembly Power Distribution, End of Cycle ....................................................................................................... 25-32

Figure 25.2-3 Typical Hot Assembly Fuel Rod Power Distribution ......................................... 25-33

Figure 25.2-4 Hot Assembly Rod Power Census for Typical Westinghouse Fuel Designs ...... 25-34

Figure 25.2-5 Relative Axial Power Distribution near Beginning of Cycle, Middle of Cycle and End of Cycle During Full Power Steady-State Conditions ......................... 25-35

Figure 25.2-6 Typical Transient Axial Power Distributions near Beginning of Cycle ............. 25-36

Figure 25.2-7 Typical Transient Axial Power Distributions near Middle of Cycle .................. 25-37

Figure 25.2-8 Typical Transient Axial Power Distributions near End of Cycle ....................... 25-38

Figure 25.2-9 [ ]a,c .......................................................................... 25-39

Figure 25.2-10 Effect of Load Follow Maneuver Period on Decay Heat Equilibrium Fraction for Various Times After Trip ................................................................ 25-40

Figure 25.2-11 Typical Measurement of Enthalpy Rise Hot Channel Factor FΔH ...................... 25-41

Figure 25.2-12 Typical Measurement of Total Peaking Factor FQ .............................................. 25-42

Figure 25.2-13 [

]a,c .......................................................................... 25-43

Figure 25.2-14 Typical WCOBRA/TRAC-TF2 Axial Power Distribution ................................ 25-44

Figure 25.7-1 Comparison of Analysis and Experiment for Scale Model Flywheel Tests ....... 25-60

Figure 25.7-2 [ ]a,c .................................................................. 25-61

Figure 26.2-1 Virgil C. Summer Vessel Profile ........................................................................ 26-23

Figure 26.2-2 Virgil C. Summer Vessel Component Elevations ............................................... 26-24

Figure 26.2-3 Virgil C. Summer Vessel Model Noding Diagram ............................................. 26-25

Figure 26.2-4 Virgil C. Summer Vessel Sections 1 through 3 .................................................. 26-26



Figure 26.2-7 Virgil C. Summer Upper Plenum Structure Map ............................................... 26-29

viii


LIST OF FIGURES (cont.)

Figure 26.2-8 Virgil C. Summer Loop Model Noding Diagram .............................................. 26-30

Figure 26.2-9 Virgil C. Summer Steam Generator Component Noding Diagram .................... 26-31

Figure 26.2-10a Virgil C. Summer Reference Case Axial Power Distribution for LBLOCA and IBLOCA ..................................................................................... 26-32

Figure 26.2-10b Virgil C. Summer Reference Case Axial Power Distribution for SBLOCA ...... 26-33

Figure 26.3-1 Beaver Valley Unit 1 Vessel Profile ................................................................... 26-47

Figure 26.3-2 Beaver Valley Unit 1 Vessel Component Elevations .......................................... 26-48

Figure 26.3-3 Beaver Valley Unit 1 Vessel Model Noding Diagram ........................................ 26-49

Figure 26.3-4 Beaver Valley Unit 1 Vessel Section 1 ............................................................... 26-50









Figure 26.3-13 Beaver Valley Unit 1 Upper Plenum Structure Map .......................................... 26-59

Figure 26.3-14 Beaver Valley Unit 1 Loop Model Noding Diagram ......................................... 26-60

Figure 26.3-15 Beaver Valley Unit 1 Steam Generator Component Noding Diagram ............... 26-61

Figure 26.3-16a Beaver Valley Unit 1 Reference Case Axial Power Distribution for LBLOCA and IBLOCA ..................................................................................... 26-62

Figure 26.3-16b Beaver Valley Unit 1 Reference Case Axial Power Distribution for SBLOCA ............................................................................................................ 26-63

Figure 27.1.1.1-1 Hot Rod Peak Cladding Temperature, CGE LBLOCA ........................................ 27-3

Figure 27.1.1.1-2 Hot Rod Peak Cladding Temperature Elevation, CGE LBLOCA ....................... 27-4

Figure 27.1.1.1-3 Break Flow, CGE LBLOCA ................................................................................ 27-5

Figure 27.1.1.1-4 RCS Pressure, CGE LBLOCA ............................................................................. 27-6

Figure 27.1.1.1-5 Accumulator Mass Flow Rate, CGE LBLOCA ................................................... 27-7

Figure 27.1.1.1-6 Vessel Fluid Mass, CGE LBLOCA ...................................................................... 27-8

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Figure 27.1.1.1-7 Safety Injection Flow Rate, CGE LBLOCA ........................................................ 27-9

Figure 27.1.1.1-8 Containment Pressure, CGE LBLOCA .............................................................. 27-10

Figure 27.1.1.2-1 Hot Rod Peak Cladding Temperature, CGE IBLOCA ....................................... 27-12

Figure 27.1.1.2-2 Break Flow, CGE IBLOCA ............................................................................... 27-13

Figure 27.1.1.2-3 RCS Pressure, CGE IBLOCA ............................................................................ 27-14

Figure 27.1.1.2-4 Accumulator Mass Flow Rate, CGE IBLOCA .................................................. 27-15

Figure 27.1.1.2-5 Vessel Fluid Mass, CGE IBLOCA ..................................................................... 27-16

Figure 27.1.1.3-1 Break Void Fraction, CGE SBLOCA ................................................................. 27-18

Figure 27.1.1.3-2 RCS Pressure, CGE SBLOCA ........................................................................... 27-19

Figure 27.1.1.3-3 Upper Head Collapsed Liquid Level, CGE SBLOCA ....................................... 27-20

Figure 27.1.1.3-4 Break Flow, CGE SBLOCA .............................................................................. 27-21

Figure 27.1.1.3-5 Hot Rod Peak Cladding Temperature, CGE SBLOCA ...................................... 27-22

Figure 27.1.1.3-6 Loop 1 Loop Seal Differential Pressure, CGE SBLOCA .................................. 27-23



Figure 27.1.2.1-1 Hot Rod Peak Cladding Temperature, DLW LBLOCA ..................................... 27-27

Figure 27.1.2.1-2 Hot Rod Peak Cladding Temperature Elevation, DLW LBLOCA ..................... 27-28

Figure 27.1.2.1-3 Break Flow, DLW LBLOCA ............................................................................. 27-29

Figure 27.1.2.1-4 RCS Pressure, DLW LBLOCA .......................................................................... 27-30

Figure 27.1.2.1-5 Accumulator Mass Flow Rate, DLW LBLOCA ................................................ 27-31

Figure 27.1.2.1-6 Vessel Fluid Mass, DLW LBLOCA ................................................................... 27-32

Figure 27.1.2.1-7 Safety Injection Flow Rate, DLW LBLOCA ..................................................... 27-33

Figure 27.1.2.1-8 Containment Pressure, DLW LBLOCA ............................................................. 27-34

Figure 27.1.2.2-1 Hot Rod Peak Cladding Temperature, DLW IBLOCA ...................................... 27-36

Figure 27.1.2.2-2 Break Flow, DLW IBLOCA ............................................................................... 27-37

Figure 27.1.2.2-3 RCS Pressure, DLW IBLOCA ........................................................................... 27-38

Figure 27.1.2.2-4 Accumulator Mass Flow Rate, DLW IBLOCA ................................................. 27-39

Figure 27.1.2.2-5 Vessel Fluid Mass, DLW IBLOCA .................................................................... 27-40

Figure 27.1.2.3-1 RCS Pressure, DLW SBLOCA .......................................................................... 27-42

x



Figure 27.1.2.3-2 Upper Head Collapsed Liquid Level, DLW SBLOCA ...................................... 27-43

Figure 27.1.2.3-3 Break Flow, DLW SBLOCA .............................................................................. 27-44

Figure 27.1.2.3-4 Hot Rod Peak Cladding Temperature, DLW SBLOCA ..................................... 27-45

Figure 27.1.2.3-5 Loop 1 Loop Seal Differential Pressure, DLW SBLOCA ................................. 27-46



Figure 27.2.1-1 Peak Cladding Temperatures, CGE LBLOCA Reference Transient .................. 27-51

Figure 27.2.1-2 Hot Rod Peak Cladding Temperature Elevation, CGE LBLOCA Reference Transient .................................................................. 27-52

Figure 27.2.1-3 Vessel Side Break Flow, CGE LBLOCA Reference Transient .......................... 27-53

Figure 27.2.1-4 Pump Side Break Flow, CGE LBLOCA Reference Transient ........................... 27-54

Figure 27.2.1-5 Lower Plenum Collapsed Liquid Level, CGE LBLOCA Reference Transient ............................................................................................ 27-55

Figure 27.2.1-6 Vapor Mass Flow Rate in Hot Assembly Near PCT Elevation, CGE LBLOCA Reference Transient .................................................................. 27-56

Figure 27.2.1-7 RCS Pressure, CGE LBLOCA Reference Transient .......................................... 27-57

Figure 27.2.1-8 Accumulator Mass Flow Rate, CGE LBLOCA Reference Transient ................ 27-58

Figure 27.2.1-9 Containment Pressure, CGE LBLOCA Reference Transient ............................. 27-59

Figure 27.2.1-10 Vessel Fluid Mass, CGE LBLOCA Reference Transient ................................... 27-60

Figure 27.2.1-11 Core Collapsed Liquid Levels, CGE LBLOCA Reference Transient ................ 27-61

Figure 27.2.1-12 Downcomer Collapsed Liquid Level, CGE LBLOCA Reference Transient ...... 27-62

Figure 27.2.1-13 Safety Injection Flow, CGE LBLOCA Reference Transient .............................. 27-63

Figure 27.2.2-1 Break Flow, CGE IBLOCA Reference Transient ............................................... 27-65

Figure 27.2.2-2 Void Fraction at the Break, CGE IBLOCA Reference Transient ....................... 27-66

Figure 27.2.2-3 RCS Pressure, CGE IBLOCA Reference Transient ........................................... 27-67

Figure 27.2.2-4 Core Collapsed Liquid Levels, CGE IBLOCA Reference Transient (2=Low Power, 3=OH/SC/FSM, 4=Guide Tube, 5=Hot Assembly) ................. 27-68

Figure 27.2.2-5 Downcomer Collapsed Liquid Levels, CGE IBLOCA Reference Transient ..... 27-69

Figure 27.2.2-6 Peak Cladding Temperatures, CGE IBLOCA Reference Transient ................... 27-70

Figure 27.2.2-7 Vapor Flowrate in the Hot Assembly, CGE IBLOCA Reference Transient ....... 27-71

Figure 27.2.2-8 Accumulator Mass Flow Rate, CGE IBLOCA Reference Transient ................. 27-72

xi



Figure 27.2.2-9 Vessel Fluid Mass, CGE IBLOCA Reference Transient .................................... 27-73

Figure 27.2.2-10 Safety Injection Flow, CGE IBLOCA Reference Transient ............................... 27-74

Figure 27.2.2-11 Safety Injection and Break Flow, CGE IBLOCA Reference Transient ............. 27-75

Figure 27.2.3-1 Void Fraction at the Break, CGE SBLOCA Reference Transient ...................... 27-78

Figure 27.2.3-2 Safety Injection Flow, CGE SBLOCA Reference Transient .............................. 27-79

Figure 27.2.3-3 RCS and Steam Generator Secondary Side Pressure, CGE SBLOCA Reference Transient............................................................................................ 27-80

Figure 27.2.3-4 Upper Head Collapsed Liquid Level, CGE SBLOCA Reference Transient ...... 27-81

Figure 27.2.3-5 Break Flow, CGE SBLOCA Reference Transient .............................................. 27-82

Figure 27.2.3-6 Core Collapsed Liquid Levels, CGE SBLOCA Reference Transient (2=Low Power, 3=OH/SC/FSM, 4=Guide Tube, 5=Hot Assembly) ................. 27-83

Figure 27.2.3-7 Hot Rod Cladding Temperature, CGE SBLOCA Reference Transient .............. 27-84

Figure 27.2.3-8 Loop 1 Loop Seal Differential Pressure, CGE SBLOCA Reference Transient ............................................................................................ 27-85



Figure 27.2.3-11 Accumulator Mass Flow Rate, CGE SBLOCA Reference Transient ................ 27-88

Figure 27.2.3-12 Vessel Fluid Mass, CGE SBLOCA Reference Transient ................................... 27-89

Figure 27.2.3-13 Safety Injection and Break Flow, CGE SBLOCA Reference Transient ............. 27-90

Figure 27.3.1-1 Peak Cladding Temperatures, DLW LBLOCA Reference Transient ................. 27-93

Figure 27.3.1-2 Hot Rod Peak Cladding Temperature Elevation, DLW LBLOCA Reference Transient............................................................................................ 27-94

Figure 27.3.1-3 Vessel Side Break Flow, DLW LBLOCA Reference Transient ......................... 27-95

Figure 27.3.1-4 Pump Side Break Flow, DLW LBLOCA Reference Transient .......................... 27-96

Figure 27.3.1-5 Lower Plenum Collapsed Liquid Level, DLW LBLOCA Reference Transient ............................................................................................ 27-97

Figure 27.3.1-6 Vapor Mass Flow in Hot Assembly Near PCT Elevation, DLW LBLOCA Reference Transient ............................................................................................ 27-98

Figure 27.3.1-7 RCS Pressure, DLW LBLOCA Reference Transient ......................................... 27-99

Figure 27.3.1-8 Accumulator Mass Flow Rate, DLW LBLOCA Reference Transient ............. 27-100

xii



Figure 27.3.1-9 Containment Pressure, DLW LBLOCA Reference Transient .......................... 27-101

Figure 27.3.1-10 Vessel Fluid Mass, DLW LBLOCA Reference Transient ................................ 27-102

Figure 27.3.1-11 Core Collapsed Liquid Levels, DLW LBLOCA Reference Transient ............. 27-103

Figure 27.3.1-12 Downcomer Collapsed Liquid Level, DLW LBLOCA Reference Transient ... 27-104

Figure 27.3.1-13 Safety Injection Flow, DLW LBLOCA Reference Transient ........................... 27-105

Figure 27.3.2-1 Break Flow, DLW IBLOCA Reference Transient ............................................ 27-107

Figure 27.3.2-2 Void Fraction at the Break, DLW IBLOCA Reference Transient .................... 27-108

Figure 27.3.2-3 RCS Pressure, DLW IBLOCA Reference Transient ........................................ 27-109

Figure 27.3.2-4 Core Collapsed Liquid Levels, DLW IBLOCA Reference Transient (2=Low Power, 3=OH/SC/FSM, 4=Guide Tube, 5=Hot Assembly) ............... 27-110

Figure 27.3.2-5 Downcomer Collapsed Liquid Levels, DLW IBLOCA Reference Transient .. 27-111

Figure 27.3.2-6 Peak Cladding Temperatures, DLW IBLOCA Reference Transient ................ 27-112

Figure 27.3.2-7 Vapor Flowrate in Hot Assembly Channel, DLW IBLOCA Reference Transient .......................................................................................... 27-113

Figure 27.3.2-8 Accumulator Mass Flow Rate, DLW IBLOCA Reference Transient ............... 27-114

Figure 27.3.2-9 Vessel Fluid Mass, DLW IBLOCA Reference Transient ................................. 27-115

Figure 27.3.2-10 Safety Injection Flow, DLW IBLOCA Reference Transient ............................ 27-116

Figure 27.3.2-11 Safety Injection and Break Flow, DLW IBLOCA Reference Transient ........... 27-117

Figure 27.3.3-1 Void Fraction at the Break, DLW SBLOCA Reference Transient ................... 27-120

Figure 27.3.3-2 Safety Injection Flow, DLW SBLOCA Reference Transient ........................... 27-121

Figure 27.3.3-3 RCS and Steam Generator Secondary Side Pressure, DLW SBLOCA Reference Transient.......................................................................................... 27-122

Figure 27.3.3-4 Upper Head Collapsed Liquid Level, DLW SBLOCA Reference Transient ... 27-123

Figure 27.3.3-5 Break Flow, DLW SBLOCA Reference Transient ........................................... 27-124

Figure 27.3.3-6 Core Collapsed Liquid Levels, DLW SBLOCA Reference Transient (2=Low Power, 3=OH/SC/FSM, 4=Guide Tube, 5=Hot Assembly) ............... 27-125

Figure 27.3.3-7 Hot Rod Cladding Temperature, DLW SBLOCA Reference Transient ........... 27-126

Figure 27.3.3-8 Loop 1 Loop Seal Differential Pressure, DLW SBLOCA Reference Transient .......................................................................................... 27-127


xiii




Figure 27.3.3-11 Accumulator Mass Flow Rate, DLW SBLOCA Reference Transient .............. 27-130

Figure 27.3.3-12 Vessel Fluid Mass, DLW SBLOCA Reference Transient ................................ 27-131

Figure 27.3.3-13 Safety Injection Flow and Break Flow, DLW SBLOCA Reference Transient .......................................................................................... 27-132

Figure 28.1.1-1 Axial Power Distribution, CGE Axial Power Distribution Sensitivity ................ 28-5

Figure 28.1.1-2 Rod 1 Peak Cladding Temperatures, CGE Axial Power Distribution Sensitivity ........................................................................................ 28-6

Figure 28.1.1-3 Peak Cladding Temperature Location, CGE Axial Power Distribution Sensitivity ........................................................................................ 28-7

Figure 28.1.1-4 Lower Plenum Collapsed Liquid Level, CGE Axial Power Distribution Sensitivity ........................................................................................ 28-8

Figure 28.1.1-5 Hot Assembly Collapsed Liquid Level, CGE Axial Power Distribution Sensitivity ........................................................................................ 28-9

Figure 28.1.1-6 Vessel Fluid Mass, CGE Axial Power Distribution Sensitivity ......................... 28-10

Figure 28.1.1-7 Axial Power Distribution, DLW Axial Power Distribution Sensitivity ............. 28-11

Figure 28.1.1-8 Peak Cladding Temperatures, DLW Axial Power Distribution Sensitivity ........ 28-12

Figure 28.1.1-9 Peak Cladding Temperature Location, DLW Axial Power Distribution Sensitivity ...................................................................................... 28-13

Figure 28.1.1-10 Lower Plenum Collapsed Liquid Level, DLW Axial Power Distribution Sensitivity ...................................................................................... 28-14

Figure 28.1.1-11 Hot Assembly Collapsed Liquid Level, DLW Axial Power Distribution Sensitivity ...................................................................................... 28-15

Figure 28.1.1-12 Vessel Fluid Mass, DLW Axial Power Distribution Sensitivity ......................... 28-16

Figure 28.1.2-1 Safety Injection Flow, CGE Offsite Power Availability Sensitivity ................... 28-19

Figure 28.1.2-2 Intact Loop Pump Speed, CGE Offsite Power Availability Sensitivity ............. 28-20

Figure 28.1.2-3 Broken Loop Pump Speed, CGE Offsite Power Availability Sensitivity ........... 28-21

Figure 28.1.2-4 Accumulator and Safety Injection Flow Rates, CGE Offsite Power Availability Sensitivity ....................................................................................... 28-22

Figure 28.1.2-5 Hot Assembly Vapor Mass Flow Rate, CGE Offsite Power Availability Sensitivity ....................................................................................... 28-23

Figure 28.1.2-6 Peak Cladding Temperatures, CGE Offsite Power Availability Sensitivity ....... 28-24

xiv



Figure 28.1.2-7 Safety Injection Flow, DLW Offsite Power Availability Study .......................... 28-25

Figure 28.1.2-8 Intact Loop Pump Speed, DLW Offsite Power Availability Study .................... 28-26

Figure 28.1.2-9 Broken Loop Pump Speed, DLW Offsite Power Availability Study .................. 28-27

Figure 28.1.2-10 Peak Cladding Temperature, DLW Offsite Power Availability Study................ 28-28

Figure 28.1.2-11 Hot Assembly Vapor Mass Flow Rate, DLW Offsite Power Availability Study .................................................................................... 28-29

Figure 28.1.2-12 Accumulator and Safety Injection Flow Rates, DLW Offsite Power Availability Sensitivity ....................................................................................... 28-30

Figure 28.1.2-13 Lower Plenum Collapsed Liquid Level, DLW Offsite Power Availability Study .................................................................................... 28-31

Figure 28.1.3-1 Vessel Fluid Mass, run010 of CGE Timestep Sensitivity Study (DTMAX) ...... 28-35

Figure 28.1.3-2 Peak Cladding Temperature, run010 of CGE Timestep Sensitivity Study (DTMAX) .......................................................................................................... 28-36

Figure 28.1.3-3 Vessel Fluid Mass, run008 of CGE Timestep Sensitivity Study (DTMAX) ...... 28-37

Figure 28.1.3-4 Peak Cladding Temperature, run008 of CGE Timestep Sensitivity Study (DTMAX) .......................................................................................................... 28-38

Figure 28.1.3-5 Vessel Fluid Mass, run004 of DLW Timestep Sensitivity Study (DTMAX) ..... 28-39

Figure 28.1.3-6 Peak Cladding Temperature, run004 of DLW Timestep Sensitivity Study (DTMAX) .......................................................................................................... 28-40

Figure 28.1.3-7 Vessel Fluid Mass, run010 of DLW Timestep Sensitivity Study (DTMAX) .......................................................................................................... 28-41

Figure 28.1.3-8 Peak Cladding Temperature, run010 of DLW Timestep Sensitivity Study (DTMAX) .......................................................................................................... 28-42

Figure 28.1.4-1 [ ]a,c ................................................................................................... 28-46

Figure 28.1.4-2 [ ]a,c ................................................................................................... 28-47

Figure 28.1.4-3 [ ]a,c ................................................................................................. 28-48

Figure 28.1.4-4 [ ]a,c ................................................................................................. 28-49

Figure 28.1.4-5 [ ]a,c ...................................................................... 28-50

xv



Figure 28.1.4-6 [ ]a,c ...................................................................... 28-51

Figure 28.1.4-7 [ ]a,c ...................................................................... 28-52

Figure 28.1.4-8 [ ]a,c ................................................................................................... 28-53

Figure 28.1.4-9 [ ]a,c ................................................................................................... 28-54

Figure 28.1.4-10 [ ]a,c ......................................................................................... 28-55

Figure 28.1.4-11 [ ]a,c ......................................................................................... 28-56

Figure 28.1.4-12 [ ]a,c ....................................................................................... 28-57

Figure 28.1.4-13 [ ]a,c ....................................................................................... 28-58

Figure 28.1.4-14 [ ]a,c ......................................................................................... 28-59

Figure 28.1.4-15 [ ]a,c ......................................................................................... 28-60

Figure 28.1.4-16 [ ]a,c ......................................................................................... 28-61

Figure 28.1.4-17 [ ]a,c ......................................................................................... 28-62

Figure 28.1.4-18 [ ]a,c ......................................................................................... 28-63

Figure 28.1.4-19 [ ]a,c ................................................................................................... 28-64

Figure 28.1.4-20 [ ]a,c ................................................................................................... 28-65

Figure 28.1.4-21 [ ]a,c ................................................................................................. 28-66

Figure 28.1.4-22 [ ]a,c ....... 28-67

Figure 28.1.4-23 [ ]a,c .............................................................. 28-68

xvi



Figure 28.1.4-24 [ ]a,c ................................................................................................... 28-69

Figure 28.1.4-25 [ ]a,c ................................................................................................... 28-70

Figure 28.1.4-26 [ ]a,c ................................................................................................... 28-71

Figure 28.1.4-27 [ ]a,c ................................................................................................... 28-72

Figure 28.1.4-28 [ ]a,c ......................................................................................... 28-73

Figure 28.1.4-29 [ ]a,c ......................................................................................... 28-74

Figure 28.1.4-30 [ ]a,c ....................................................................................... 28-75

Figure 28.1.4-31 [ ]a,c ....................................................................................... 28-76

Figure 28.1.4-32 [ ]a,c ............................................................ 28-77

Figure 28.1.4-33 [ ]a,c ......................................................................................... 28-78

Figure 28.1.4-34 [ ]a,c ......................................................................................... 28-79

Figure 28.1.4-35 [ ]a,c ......................................................................................... 28-80

Figure 28.1.4-36 [ ]a,c ......................................................................................... 28-81

Figure 28.1.5-1 [ ]a,c ......................................................................................................... 28-84

Figure 28.1.5-2 [ ]a,c ............ 28-85

Figure 28.1.5-3 [ ]a,c ............ 28-86

Figure 28.1.5-4 [ ]a,c ......................................................................................................... 28-87

Figure 28.1.5-5 [ ]a,c ............ 28-88

Figure 28.1.5-6 [ ]a,c ............ 28-89

xvii



Figure 28.1.5-7 [ ]a,c ......................................................................................................... 28-90

Figure 28.1.5-8 [ ]a,c ............ 28-91

Figure 28.1.5-9 [ ]a,c ............ 28-92

Figure 28.1.6-1 [ ]a,c ................... 28-95

Figure 28.1.6-2 [ ]a,c ................... 28-96

Figure 28.1.6-3 [ ]a,c .................................................................................... 28-97

Figure 28.1.6-4 [ ]a,c ........ 28-98

Figure 28.1.6-5 [ ]a,c .................................................................................... 28-99

Figure 28.1.6-6 [ ]a,c .................................................................................. 28-100

Figure 28.1.6-7 [ ]a,c ................................ 28-101

Figure 28.1.6-8 [ ]a,c .......................................................................... 28-102

Figure 28.1.6-9 [ ]a,c ..................................................................................................... 28-103

Figure 28.1.6-10 [ ]a,c ..................................................................................................... 28-104

Figure 28.1.6-11 [ ]a,c ............... 28-105

Figure 28.1.6-12 [ ]a,c ..................................................................................................... 28-106

Figure 28.1.6-13 [ ]a,c ..................................................................................................... 28-107

Figure 28.2.2-1 [ ]a,c .............................................................................. 28-110

Figure 28.2.2-2 [ ]a,c .............................................................................. 28-111

Figure 28.2.2-3 [ ]a,c .............................................................................. 28-112

Figure 28.2.2-4 [ ]a,c .............................................................................. 28-113

xviii



Figure 28.2.2-5 [ ]a,c .............................................................................. 28-114

Figure 28.2.2-6 [ ]a,c .............................................................................. 28-115

Figure 28.2.2-7 [ ]a,c ................................................................... 28-116

Figure 28.2.2-8 [ ]a,c ................................................................... 28-117

Figure 28.2.2-9 [ ]a,c ................................................................... 28-118

Figure 28.2.2-10 [ ]a,c .............................................................................. 28-119

Figure 28.2.2-11 [ ]a,c .............................................................................. 28-120

Figure 28.2.2-12 [ ]a,c .............................................................................. 28-121

Figure 28.2.2-13 [ ]a,c ............................................................................. 28-122

Figure 28.2.2-14 [ ]a,c .............................................................................. 28-123

Figure 28.2.2-15 [ ]a,c .............................................................................. 28-124

Figure 28.2.2-16 [ ]a,c ................................................................... 28-125

Figure 28.2.2-17 [ ]a,c ................................................................... 28-126

Figure 28.2.2-18 [ ]a,c ................................................................... 28-127

Figure 28.2.3-1 [ ]a,c ............................................................................................ 28-130

Figure 28.2.3-2 [ ]a,c ......................................................................... 28-131

Figure 28.2.3-3 [ ]a,c ..................................................... 28-132

xix



Figure 28.2.3-4 [ ]a,c ..................................................... 28-133

Figure 28.2.3-5 [ ]a,c ............................................................................................ 28-134

Figure 28.2.3-6 [ ]a,c ..................................................... 28-135

Figure 28.2.3-7 [ ]a,c ............................................................................................ 28-136

Figure 28.2.3-8 [ ]a,c ......................................................................... 28-137

Figure 28.2.3-9 [ ]a,c ............................................................................................ 28-138

Figure 28.2.3-10 [ ]a,c ......................................................................... 28-139

Figure 28.2.3-11 [ ]a,c ............................................................................................ 28-140

Figure 28.2.3-12 [ ]a,c ............................................................................................ 28-141

Figure 28.2.3-13 [ ]a,c ............................................................................................ 28-142

Figure 28.2.3-14 [ ]a,c .......................................... 28-143

Figure 28.2.3-15 [ ]a,c ............................................................................................ 28-144

Figure 28.2.3-16 [ ]a,c ......................................................................... 28-145

Figure 28.2.3-17 [ ]a,c ............................................................................................ 28-146

Figure 28.2.3-18 [ ]a,c ..................................................... 28-147

Figure 28.2.3-19 [ ]a,c ............................................................................................ 28-148

Figure 28.2.3-20 [ ]a,c ......................................................................... 28-149

Figure 28.2.4-1 [ ]a,c ..................... 28-151

xx



Figure 28.2.4-2 [ ]a,c ......................................................................... 28-152

Figure 28.2.4-3 [ ]a,c ............................................................................................ 28-153

Figure 28.2.4-4 [ ]a,c ....................... 28-154

Figure 28.2.4-5 [ ]a,c ............................................................ 28-155

Figure 28.2.4-6 [ ]a,c ............................................................................................... 28-156

Figure 28.2.5-1 [ ]a,c .................................................................................. 28-158

Figure 28.2.5-2 [ ]a,c .................................................................................. 28-159

Figure 28.2.5-3 [ ]a,c ................. 28-160

Figure 28.2.6-1 [ ]a,c ............................. 28-162

Figure 28.2.6-2 [ ]a,c ...... 28-163

Figure 28.2.6-3 [ ]a,c .......... 28-164

Figure 28.2.6-4 [ ]a,c .......... 28-165

Figure 28.2.6-5 [ ]a,c ................................................. 28-166

Figure 28.2.6-6 [ ]a,c ................................ 28-167

Figure 28.2.6-7 [ ]a,c .......... 28-168

Figure 28.2.6-8 [ ]a,c .......... 28-169

Figure 28.2.6-9 [ ]a,c .......... 28-170

Figure 28.2.7-1 [ ]a,c ................................ 28-172

Figure 28.2.7-2 [ ]a,c ............................................................................... 28-173

Figure 28.2.7-3 [ ]a,c .................................... 28-174

xxi



Figure 28.2.7-4 [ ]a,c ...................... 28-175

Figure 28.2.7-5 [ ]a,c ......................... 28-176

Figure 28.2.7-6 [ ]a,c .......... 28-177

Figure 28.2.7-7 [ ]a,c ................................ 28-178

Figure 28.2.7-8 [ ]a,c ............................................................................... 28-179

Figure 28.2.7-9 [ ]a,c ................................... 28-180

Figure 28.2.7-10 [ ]a,c ............ 28-181

Figure 28.2.7-11 [ ]a,c ......................... 28-182

Figure 28.2.7-12 [ ]a,c ......... 28-183

Figure 28.2.7-13 [ ]a,c ............................................................................... 28-184

Figure 28.2.7-14 [ ]a,c ............................................................................... 28-185

Figure 28.2.7-15 [ ]a,c ............................................................................... 28-186

Figure 28.2.8-1 [ ]a,c ............................................................... 28-189

Figure 28.2.8-2 [ ]a,c ................................................................................ 28-190

Figure 28.2.8-3 [ ]a,c ................................................................................ 28-191

Figure 28.2.8-4 [ ]a,c ................................................................................ 28-192

Figure 28.2.8-5 [ ]a,c ..................................... 28-193

Figure 28.2.8-6 [ ]a,c ..................................... 28-194

Figure 28.2.8-7 [ ]a,c .................................................................................................. 28-195

Figure 28.2.8-8 [ ]a,c .................................................................................................. 28-196

Figure 28.2.8-9 [ ]a,c ................................................................................ 28-197

xxii



Figure 28.2.8-10 [ ]a,c ................................................................................ 28-198

Figure 28.2.8-11 [ ]a,c ................................................................................ 28-199

Figure 28.2.8-12 [ ]a,c ................................................................................ 28-200

Figure 28.2.8-13 [ ]a,c ............................................................... 28-201

Figure 28.2.8-14 [ ]a,c ........................... 28-202

Figure 28.2.8-15 [ ]a,c ................................................................................ 28-203

Figure 28.2.8-16 [ ]a,c ................................................................................ 28-204

Figure 28.2.9-1 [ ]a,c ................................................ 28-207

Figure 28.2.9-2 [ ]a,c ................................................ 28-208

Figure 28.2.9-3 [ ]a,c ................................................ 28-209

Figure 28.2.9-4 [ ]a,c ................................................ 28-210

Figure 28.2.9-5 [ ]a,c ............................................................................................ 28-211

Figure 28.2.9-6 [ ]a,c ............................................................................................ 28-212

Figure 28.2.9-7 [ ]a,c ......................................................................... 28-213

Figure 28.2.9-8 [ ]a,c ............................................................................................ 28-214

Figure 28.2.9-9 [ ]a,c ................................................ 28-215

Figure 28.2.9-10 [ ]a,c ............................................................................................ 28-216

xxiii



Figure 28.2.9-11 [ ]a,c ............................................................................................ 28-217

Figure 28.2.9-12 [ ]a,c ......................................................................... 28-218

Figure 28.2.10-1 [ ]a,c ................................... 28-220

Figure 28.2.10-2 [ ]a,c ........................................................................ 28-221

Figure 28.2.10-3 [ ]a,c ........................................................................ 28-222

Figure 28.2.10-4 [ ]a,c ........................................................................ 28-223

Figure 28.2.10-5 [ ]a,c ........................................................................ 28-224

Figure 28.2.10-6 [ ]a,c ........................................................................ 28-225

Figure 28.2.10-7 [ ]a,c ........................................................................ 28-226

Figure 28.2.10-8 [ ]a,c ........ 28-227

Figure 28.2.10-9 [ ]a,c .................................. 28-228

Figure 28.2.10-10 [ ]a,c ........................................................................ 28-229

Figure 28.2.10-11 [ ]a,c ............................................ 28-230

Figure 28.2.10-12 [ ]a,c ............................................ 28-231

Figure 28.2.10-13 [ ]a,c .................................. 28-232

Figure 28.2.10-14 [ ]a,c .................................. 28-233

Figure 28.2.10-15 [ ]a,c ......................................................................................... 28-234

Figure 28.2.10-16 [ ]a,c ....... 28-235

Figure 28.2.11-1 [ ]a,c ............... 28-237

xxiv



Figure 28.2.11-2 [ ]a,c ............... 28-238

Figure 28.2.11-3 [ ]a,c ............... 28-239

Figure 28.2.11-4 [ ]a,c ............... 28-240

Figure 28.2.11-5 [ ]a,c ............... 28-241

Figure 28.2.11-6 [ ]a,c ............... 28-242

Figure 28.2.11-7 [ ]a,c ................................... 28-243

Figure 28.2.12-1 [ ]a,c ............................................... 28-249

Figure 28.2.12-2 [ ]a,c ........................ 28-250

Figure 28.2.12-3 [ ]a,c .......................... 28-251

Figure 28.2.12-4 [ ]a,c ....................................................................... 28-252

Figure 28.2.12-5 [ ]a,c .......................... 28-253

Figure 28.2.12-6 [ ]a,c ..................................... 28-254

Figure 28.2.12-7 [ ]a,c ..................... 28-255

Figure 28.2.12-8 [ ]a,c .............................................. 28-256

Figure 28.2.12-9 [ ]a,c ....................... 28-257

Figure 28.2.12-10 [ ]a,c .......................... 28-258

Figure 28.2.12-11 [ ]a,c ...................................................................... 28-259

Figure 28.2.12-12 [ ]a,c .......................... 28-260

Figure 28.2.12-13 [ ]a,c .................................... 28-261

Figure 28.2.12-14 [ ]a,c .................... 28-262

Figure 29.1.1-1 [ ]a,c ................................................... 29-14

Figure 29.1.1-2 [ ]a,c .......................................................... 29-15

Figure 29.1.1-3 [ ]a,c ........................................ 29-16

xxv



Figure 29.1.1-4 [ ]a,c .............................................. 29-17

Figure 29.1.1-5 Branchline Quality Versus Mainline Liquid Level for Horizontal Configuration ................................................................................... 29-19

Figure 29.1.1-6 Branchline Quality Versus Mainline Liquid Level for Downward-Vertical Configuration ..................................................................... 29-20

Figure 29.1.5-1 Predicted Versus Measured Level Swell for the G-1 and G-2 Boil-off Simulations with [ ]a,c .................................... 29-28

Figure 29.1.5-2 Predicted Versus Measured Level Swell for the G-2 Boil-off Simulations with [ ]a,c ................................... 29-29

Figure 29.1.5-3 Differential Pressure in the Test Bundle for [ ]a,c, FLECHT-SEASET Test 31504 .......................................................................... 29-30

Figure 29.1.5-4 Quench Profile for [ ]a,c, FLECHT-SEASET Test 31504 .......................................................................... 29-31

Figure 29.1.8-1 Dispersed Flow Cooling ..................................................................................... 29-36

Figure 29.1.8-2 Inverted Annular Cooling ................................................................................... 29-36

Figure 29.1.8-3 Histogram of Tmin Values Based on G-1 and G-2 Test Data [

]a,c ........................ 29-37

Figure 29.1.8-4 Tmin Variation with Re (From Appendix N, Boyack et al., 1989) ....................... 29-38

Figure 29.1.8-5 Tmin Variation with Pressure (From Appendix N, Boyack et al., 1989) .............. 29-38

Figure 29.1.8-6 Method for Determining Quench Temperature [ ]a,c ........ 29-39

Figure 29.1.8-7a Predicted vs. Measured Quench Temperatures from G-1 Blowdown Simulations ............................................................................... 29-39

Figure 29.1.8-7b Predicted vs. Measured Quench Temperatures from G-1 Blowdown Simulations with TMIN Set to Homogeneous Nucleation Temperature ............ 29-40

Figure 29.1.8-8 Predicted vs. Measured Quench Temperatures from FLECHT SEASET Forced Reflood Test Simulations ........................................ 29-40

Figure 29.1.8-9 Predicted vs. Measured Quench Temperatures from FLECHT Low Flooding Rate Forced Reflood Test Simulations ....................................... 29-41

Figure 29.1.8-10 Predicted vs. Measured Quench Temperatures from FLECHT Skewed Forced Reflood Test Simulations.......................................................... 29-41

Figure 29.1.11-1 Residual Liquid Level from UPTF Loop Seal HS_SLUG Study ...................... 29-45

xxvi



Figure 29.1.11-2 Break Spectrum Studies (3-loop PWR) Segregated Based on the Number and Which Loop Seals Clear ................................................................ 29-45

Figure 29.2.3-1 LOCA Frequency Evaluation Obtained using Expert Elicitation Presented by Tregoning, et al. (2007) ................................................................ 29-53

Figure 29.2.4-1 DEGCL Break Noding Scheme ......................................................................... 29-55

Figure 29.2.4-2 Guillotine Break Noding Used in WCOBRA/TRAC-TF2................................. 29-56

Figure 29.2.5-1 Split Break Noding Scheme ............................................................................... 29-59

Figure 29.2.5-2 Split Break Noding Used in WCOBRA/TRAC-TF2 ......................................... 29-60

Figure 29.2.5-3 Demonstration of CD1/CD2 Application for SPLIT Breaks .............................. 29-60

Figure 29.4.1-1 Maximum Rod Average Power at a Given Rod Burnup at Various Times During a Typical Cycle .............................................................. 29-78

Figure 29.4.1-2 [ ]a,c ........................ 29-79

Figure 29.4.1-3 Fuel Pellet Average Temperatures as a Function of Rod Average Burnup for 0.422-inch Outer Diameter Fuel ........................................................................ 29-80

Figure 29.4.1-4 Effect of Load Follow on FQ .............................................................................. 29-81

Figure 29.4.1-5 [

]a,c ............................................................ 29-82

Figure 29.4.1-6 [

]a,c ............................ 29-83

Figure 29.4.1-7 [

]a,c ............................................................ 29-84

Figure 29.4.1-8 [

]a,c ............................................................ 29-85

Figure 29.4.1-9 Example Bottom Skewed Axial Power Distribution [ ]a,c ......................... 29-86

Figure 29.4.1-10 Example Top Skewed Axial Power Distribution [ ]a,c ................................................ 29-87

Figure 29.4.1-11 [ ]a,c ............................................................................................... 29-88

xxvii



Figure 29.4.1-12 [

]a,c ................................................................................ 29-89

Figure 29.4.2-1 ZIRLO® Cladding Burst Temperature Data and Correlation ............................. 29-95

Figure 29.4.2-2 [ ]a,c ....................................... 29-99

Figure 29.4.2-3 [ ]a,c .............. 29-100

Figure 29.4.2-4 [ ]a,c ........................................................................................ 29-101

Figure 29.4.2-5 [ ]a,c ....................................................................................... 29-102

Figure 29.4.2-6 [ ]a,c ................................................................................... 29-103

Figure 29.4.2-7 [ ]a,c ........................................................ 29-104

Figure 29.4.2-8 [ ]a,c ......................................... 29-105

Figure 29.4.2-9 [ ]a,c ................................................... 29-106

Figure 29.4.2-10 [ ]a,c ............................ 29-107

Figure 29.4.2-11 [ ]a,c ........................................... 29-109

Figure 29.4.2-12 Distribution of Packing Fraction Data ............................................................. 29-109

Figure 29.4.2-13 [ ]a,c .................................................................................................. 29-114

Figure 29.4.2-14 [ ]a,c ............................................................................................ 29-115

Figure 29.4.3-1 [ ]a,c ......................... 29-125

Figure 29.4.3-2 [ ]a,c ........................ 29-125

Figure 29.4.3-3 Heat Transfer Coefficient vs. Time from FLECHT 31805, 6 ft ....................... 29-126

Figure 29.4.3-4 Predicted vs. Measured Heat Transfer Coefficients from Forced Reflood Tests ........................................................................................ 29-127

xxviii



Figure 29.4.3-5 [ ]a,c .................................... 29-127

Figure 29.4.3-6 FLECHT 31203 6-ft Elevation Cladding Temperature Comparison for [ ]a,c Heat Transfer Multiplier of [ ]a,c ........... 29-128















Figure 29.4.3-21 FLECHT 31805 8-ft Elevation Cladding Temperature Comparison for [ ]a,c Heat Transfer Multiplier of [ ]a,c .......... 29-135

xxix





Figure 31.1-1 Description of Break Area Regions ...................................................................... 31-5

Figure 31.2-1 [ ]a,c ........................................................ 31-9

Figure 31.2-2 [ ]a,c ............ 31-10

Figure 31.2-3 [ ]a,c ..................................... 31-11

Figure 31.2-4 [ ]a,c ............ 31-12

Figure 31.3-1 [ ]a,c ..................................................................... 31-19

Figure 31.3-2 [

]a,c ....................... 31-20

Figure 31.3-3 [ ]a,c .................................................. 31-21

Figure 31.3-4 [ ]a,c........................................................................................................ 31-22

Figure 31.3-5 [ ]a,c........................................................................................................ 31-23

Figure 31.3-6 [ ]a,c ..................... 31-24

Figure 31.3-7 [ ]a,c .............................................. 31-25

Figure 31.3-8 [ ]a,c........................................................................................................ 31-26

Figure 31.3-9 [ ]a,c....................... 31-27

Figure 31.3-10 [ ]a,c........................................................................................................ 31-28

Figure 31.3-11 [ ]a,c........................................................................................................ 31-29

Figure 31.3-12 [ ]a,c .............. 31-30

xxx



Figure 31.3-13 [ ]a,c ..................... 31-31

Figure 31.3-14 [ ]a,c........................................................................................................ 31-32

Figure 31.3-15 [ ]a,c ........................ 31-33

Figure 31.3-16 [ ]a,c ......................................... 31-34

Figure 31.3-17 [ ]a,c .................... 31-35

Figure 31.3-18 [ ]a,c ......................................... 31-36

Figure 31.3-19 [ ]a,c .................... 31-37

Figure 31.3-20 [ ]a,c ......................................... 31-38

Figure 31.3-21 [ ]a,c .................... 31-39

Figure 31.3-22 [ ]a,c .................................................. 31-40

Figure 31.4-1 [ ]a,c ...................................................................................................... 31-45

Figure 31.4-2 [ ]a,c .................... 31-46

Figure 31.4-3 [ ]a,c .................. 31-47

Figure 31.4-4 [ ]a,c ........................ 31-48

Figure 31.4-5 [ ]a,c ...................................................................................................... 31-49

Figure 31.4-6 [ ]a,c ........ 31-50

Figure 31.4-7 [ ]a,c ................................................................................ 31-51

Figure 31.4-8 [ ]a,c ..... 31-52

Figure 31.4-9 [ ]a,c ............................. 31-53

Figure 31.4-10 [

]a,c ........................................................ 31-54

Figure 31.4-11 [ ]a,c ....................................................................... 31-55

25-1


25 PLANT SOURCES OF UNCERTAINTY

We have, to this point, assessed the ability of WCOBRA/TRAC-TF2 to simulate the key phenomena identified in the Phenomena Identification and Ranking Table (PIRT). In addition, it has been demonstrated that compensating errors or bias, due to the increase in scale from the experiments to the Pressurized Water Reactor (PWR), result in a more conservative estimate of the Loss-of-Coolant Accident (LOCA) analysis results relative to several key phenomena. However, there may be differences in PWR response to the LOCA, which may result in some models being more important for the PWR than for the experiment. In addition, variability in plant initial and boundary conditions introduce additional uncertainty. In this section, these additional aspects are discussed. The objective of this section is to develop a plan for performing various sensitivity or scoping studies with the PWR models described in Section 26, in order to identify those parameters which have an important influence on the calculation of the Peak Cladding Temperature (PCT) and Maximum Local Oxidation (MLO) in the PWR, and to make decisions about which variables should be considered for uncertainty propagation.

For some parameters, the uncertainty will be explicitly treated within the uncertainty analysis. For other parameters, a conservative approach may be employed (such as for the containment back-pressure).

25.1 PLANT PHYSICAL CONFIGURATION

The plant physical configuration consists of those parameters which define the geometrical and hydraulic configuration of the reactor at the time the LOCA occurs. These parameters are listed and defined below:

1. Dimensions 2. Flow resistances 3. Pressurizer location, relative to broken loop 4. Accumulator Tank Elevation 5. Hot assembly location, relative to vessel upper internals 6. Hot assembly type 7. Steam generator tube plugging level

Dimensions

Reactor dimensions, volumes, and surface areas are obtained directly from component drawings. Some variability exists in these dimensions due to tolerances and approximations which may have been made in geometrical calculations. Dimensions also vary from nominal due to thermal expansion. Thermal expansion is estimated to increase volumes by about [

]a,c

Fuel assembly grids, control rod guide tubes, and steam generator tubes may be affected, in some cases, by high stresses resulting from the combination of seismic and LOCA loads, an assumption required by the Code of Federal Regulations (CFR) 10 CFR 50, Appendix A, General Design Criterion 4. A dynamic analysis of the Reactor Coolant System (RCS) under combined seismic and LOCA loads is performed to demonstrate that key RCS components will continue to perform their safety function. Structural analyses

25-2


performed as part of the original plant design basis have confirmed that Emergency Core Cooling System (ECCS) safety function and core shutdown capability are maintained. These analyses have also indicated that for some plants, the pressure differentials and structural movements which are predicted may result in minor deformation of fuel assembly grids, control rod guide tubes, and/or steam generator tubes. In the case of the fuel assembly, some deformation of the grids in ass

wcap-16996-np-a, rev 1, 'realistic loca evaluation ... · 26.2 v. c. summer nuclear power plant ......

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